scholarly journals Influence of trehalose, glucose, fructose, and sucrose on gelatinisation and retrogradation of corn and tapioca starches

2009 ◽  
Vol 27 (No. 3) ◽  
pp. 151-157 ◽  
Author(s):  
J. Babić ◽  
D. Šubarić ◽  
B. Milicevic ◽  
D. Ačkar ◽  
M. Kopjar ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Corn Starch ◽  
Storage Temperature ◽  
Storage Period ◽  
Scanning Calorimetry ◽  
Molecular Weights ◽  
Starch Retrogradation ◽  
And Storage

The effects of trehalose, glucose, fructose, and sucrose on the gelatinisation and retrogradation properties of corn (CS) and tapioca (TS) starches were studied with differential scanning calorimetry (DSC). The results showed that the sugars affect gelatinisation and retrogradation of both starches, with the effect varying significantly between sugars. The addition of trehalose, glucose, fructose, and sucrose increased the gelatinisation temperatures and enthalpy of gelatinisation of corn and tapioca starches. The extent of increase followed the order: fructose < glucose < trehalose < sucrose with CS, and fructose < trehalose < sucrose < glucose with TS. The retrogradation studies showed that sugars of lower molecular weights (glucose and fructose) were less effective in the reduction of retrogradation than those of higher molecular weights (sucrose and trehalose). Trehalose retarded retrogradation of both corn and tapioca starches under all conditions investigated. Sucrose had the same effect on the corn starch retrogradation. The effects of other sugars depended on the type of starch, storage period, and storage temperature.

scholarly journals Staling of sponge cakes with added emulsifiers

2020 ◽  
Author(s):  
Maria Marudova ◽  
Stanko Stankov ◽  
Marianna Baeva
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Differential Thermal Analysis ◽  
Control Sample ◽  
Bound Water ◽  
Storage Period ◽  
Scanning Calorimetry ◽  
Retarding Effect ◽  
Starch Retrogradation ◽  
Endothermic Transition

AbstractThe effect of three types of emulsifiers (polyglycerol monostearate ester – E475, sucrose stearate ester – E473 and modified inulin palmitate ester – HP-25) on the starch retrogradation in sponge cake (SC) during storage was investigated. The method of differential scanning calorimetry (DSC) was applied to determine the changes in the starch retrogradation during the staling process. The retrogradation temperature and the enthalpy of the endothermic transition decreased when emulsifiers were added. The lowest values of the enthalpy for the whole storage period were found for SC with 1% HP-25. The methods of differential thermal analysis (DTA) and thermogravimetry analysis (TGA) showed significantly bigger (1.43 times) amount of strongly bound water in the crumb of the SC with E475 and HP-25 in comparison to the control sample on the sixth day of storage. Based on our results, emulsifiers possessed retarding effect on the starch retrogradation and extend the shelf-life of the SC.

Changes in Selected Nutrients and Microstructure of White Starch Quality Maize and Common Maize During Tortilla Preparation and Storage

2004 ◽  
Vol 10 (2) ◽  
pp. 79-87 ◽  
Author(s):  
R. Mora-Escobedo ◽  
P. Osorio-Diaz ◽  
M. I. Garcia-Rosas ◽  
A. Bello-Perez ◽  
H. Hernandez-Unzon
Keyword(s):  
Differential Scanning Calorimetry ◽  
High Temperature ◽  
Structural Changes ◽  
Prolonged Storage ◽  
Starch Granules ◽  
Scanning Calorimetry ◽  
Starch Quality ◽  
Starch Retrogradation ◽  
And Storage ◽  
Starch Crystallinity

Raw maize, masa, and fresh and stored tortillas of white starch quality maize (Costeno) and common maize were analysed for chemical composition, dietary fibre, digestible (DS) and resistant (RS) starches. Changes in starch crystallinity and microstructure were also evaluated. Protein content was lower in masa and tortillas than in the original maize samples. Insoluble (IDF) and soluble (SDF) dietary fibres were higher in Costeno than in common maize, but stored tortillas showed the highest value in both samples. DS decreased and RS increased during tortillas storage, made with both starches. The development of RS explained the observed decrease in DS in masa (enthalpy of gelatinisation). Differential scanning calorimetry studies showed peak gelatinisation temperatures (Tp) of 75.1 and 69.4 C for Costeno and common maize respectively. Masa of common maize showed a second transition endotherm (Tp, 108.9 C) which corresponded to amylose–lipid complexation. Tortillas with 5 and 10 days of storage showed an endothermic event at 53 and 55.7, and 54.5 and 59.9 C for Costeno and common maize respectively, due to starch retrogradation. These values were in accordance with the higher total RS contents recorded after prolonged storage. Microscopic structures for masa and fresh tortillas showed that the high temperature imposed on the masa and the influence of mechanical stress during tortillas making were great enough to disrupt starch granules. In general, structural changes were in agreement with changes in starch.

scholarly journals Changes in Particle Size, Sedimentation, and Protein Microstructure of Ultra-High-Temperature Skim Milk Considering Plasmin Concentration and Storage Temperature

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2339
Author(s):  
So-Yul Yun ◽  
Jee-Young Imm
Keyword(s):  
Particle Size ◽  
High Temperature ◽  
Storage Temperature ◽  
Whey Proteins ◽  
Skim Milk ◽  
Storage Period ◽  
Sediment Analysis ◽  
Sediment Formation ◽  
And Storage ◽  
Ultra High Temperature

Age gelation is a major quality defect in ultra-high-temperature (UHT) pasteurized milk during extended storage. Changes in plasmin (PL)-induced sedimentation were investigated during storage (23 °C and 37 °C, four weeks) of UHT skim milk treated with PL (2.5, 10, and 15 U/L). The increase in particle size and broadening of the particle size distribution of samples during storage were dependent on the PL concentration, storage period, and storage temperature. Sediment analysis indicated that elevated storage temperature accelerated protein sedimentation. The initial PL concentration was positively correlated with the amount of protein sediment in samples stored at 23 °C for four weeks (r = 0.615; p < 0.01), whereas this correlation was negative in samples stored at 37 °C for the same time (r = −0.358; p < 0.01) due to extensive proteolysis. SDS-PAGE revealed that whey proteins remained soluble over storage at 23 °C for four weeks, but they mostly disappeared from the soluble phase of PL-added samples after two weeks’ storage at 37 °C. Transmission electron micrographs of PL-containing UHT skim milk during storage at different temperatures supported the trend of sediment analysis well. Based on the Fourier transform infrared spectra of UHT skim milk stored at 23 °C for three weeks, PL-induced particle size enlargement was due to protein aggregation and the formation of intermolecular β-sheet structures, which contributed to casein destabilization, leading to sediment formation.

scholarly journals Pengujian Umur Simpan Kopi Arabika Bubuk Pada Jenis Kemasan dan Suhu Simpan Yang Berbeda

2021 ◽  
Vol 8 (1) ◽  
pp. 37
Author(s):  
Elsera Br Tarigan ◽  
Edi Wardiana ◽  
Handi Supriadi
Keyword(s):  
Shelf Life ◽  
Storage Temperature ◽  
Storage Period ◽  
Fat Content ◽  
Test Method ◽  
Life Test ◽  
Coffee Plantations ◽  
Randomized Design ◽  
Completely Randomized Design ◽  
And Storage

<p><em>Coffee is a beverage that is widely consumed around the world. Proper packaging and storage temperature may extend shelf life of ground coffee. The study aimed to analyze the shelf life of ground Arabica coffee stored in different packaging types and temperature, conducted at smallholder coffee plantations in Garut Regency and the Integrated Laboratory of Indonesian Industrial and Beverage Crops Research Institute, Sukabumi, from June to August 2018. A completely randomized design in factorial was used with 3 factors and 2 replications. The first factor was the packaging type  which consisted of 3 types: thick alumunium  foil 65</em><em>m</em><em> (AF65), thick alumunium  foil 130</em><em>m</em><em> (AF130), and thick lamination 114</em><em>m</em><em> (L144). The second factor was the storage temperature which consisted of 3 levels: 25 <sup>o</sup>C, 35 <sup>o</sup>C, and 45 <sup>o</sup>C, while the third factor was the storage period which consisted of 5 levels: coffee unstored, and coffee stored for 2 weeks, 4 weeks, 6 weeks, and 8 weeks. The variables observed were the water and fat content, and the analysis of shelf life was carried out using the ASLT (Accelerated Shelf Life Test) method. The results showed that during storage, the water content increased, whereas the fat content decreased. Fat content is a critical variable in determining the shelf life of coffee. The coffee in AF130 packaging has longer shelf life than in AF65 and L144. To extend the shelf life of coffee packaged in AF130 and L144 is best kept at 45<sup> o</sup>C whereas coffee in AF65 packaging  is ideally at 25<sup> o</sup>C.</em></p>

scholarly journals Seminal and spermatic characteristics of fresh semen and the effects of sperm cooling in Steindachneridion melanodermatum (Garavello, 2005)

2015 ◽  
Vol 36 (6Supl2) ◽  
pp. 4493
Author(s):  
Ronan Maciel Marcos ◽  
Giovano Neumann ◽  
Cesar Pereira Rebechi de Toledo ◽  
João Marcos Sena ◽  
Gilmar Baumgartner ◽  
...  
Keyword(s):  
Sperm Motility ◽  
Storage Temperature ◽  
Sperm Concentration ◽  
Plasma Osmolality ◽  
Storage Period ◽  
Sperm Velocity ◽  
Powdered Milk ◽  
Sperm Activation ◽  
And Storage ◽  
Fresh Semen

<p>This study describes the seminal and spermatic characteristics of fresh semen of <em>Steindachneridion melanodermatum </em>and investigates the effects of dilution, temperature, and storage period on its spermatic parameters. Sperm samples were collected from nine hormonally-induced males. The following parameters in fresh sperm were analyzed: seminal plasma osmolality (OSM), seminal pH, sperm motility (MOT), sperm velocity (SV) (including sperm curvilinear velocity (CVV), sperm straight-line velocity (SLV), and sperm average path velocity (APV)), total time of sperm motility (TEMP), sperm concentration (CONC), and index of sperm normality (NORM). Sperm samples from each male were diluted in a solution containing 5% fructose and 5% powdered milk, and stored at 10°C and 25°C. The same was carried out for sperm samples not subjected to dilution. From these samples, MOT, CVV, SLV, APV, SV, and TEMP were measured after 0 h, 5 h, 9 h, 18 h, 27 h, 36 h, 45 h, and 54 h. Males released 11.74 ± 5.38 mL of sperm, with an osmolality of 258.78 ± 29.36 mOsm.kg-1 and pH of 7.11 ± 0.31. The sperm presented a MOT of 99.86 ± 0.31% at a concentration of 1.03 × 1010 ± 3.65 × 109 spermatozoa.mL-1 with CVV of 185.58 ± 14.11 ?m.s-1, SLV of 49.15 ± 4.66 ?m.s-1, APV of 87.02 ± 4.13 ?m.s-1, SV of 106.52 ± 4.45 ?m.s-1, TEMP of 79.31 ± 5.62 s, NORM of 75.81 ± 5.71%. The results indicate that sperm motility, sperm velocity, and total time of sperm activation were affected by dilution, storage temperature, and storage period (p &lt; 0.05). Procedures for semen storage should be performed with undiluted sperm cooled at 10°C, or kept undiluted at 25°C for up to 27 h.</p>

Comparison of Electron and Infrared Spectroscopy with Thermal Analysis to Study Molecular Weight Effects in PVC-PMMA Blends

1993 ◽  
Vol 47 (10) ◽  
pp. 1636-1642 ◽  
Author(s):  
Cindy A. Burkhardt ◽  
Joseph A. Gardella
Keyword(s):  
Thermal Analysis ◽  
Molecular Weight ◽  
Differential Scanning Calorimetry ◽  
Infrared Spectroscopy ◽  
Lower Molecular Weight ◽  
Scanning Calorimetry ◽  
Molecular Weights ◽  
Solvent Cast ◽  
Pmma Blends

The effects of homopolymer molecular weight on the miscibility of PVC/PMMA solvent cast blends were studied. Two significantly different molecular weights were chosen for each of the homopolymers, and a series of blends was prepared from the four possible homopolymer-homopolymer combinations. Angle-dependent ESCA results suggest that the surfaces of the blends are enriched with PMMA. The extent of this enrichment is dependent on molecular weight, with the most enrichment seen in blends containing the lower-molecular-weight PMMA homopolymer. Differential scanning calorimetry (DSC) results are also presented.

scholarly journals Properties of corn starch subjected hydrothermal modification

2017 ◽  
Vol 31 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Artur Gryszkin ◽  
Tomasz Zięba ◽  
Małgorzata Kapelko-Żeberska
Keyword(s):  
Differential Scanning Calorimetry ◽  
Corn Starch ◽  
Heating Temperature ◽  
Thermal Characteristics ◽  
Scanning Calorimetry ◽  
Water Dispersion ◽  
Swelling Power ◽  
Hydrothermal Modification ◽  
Starch Paste

Abstract The objective of this study was to determine the effect of heating a water dispersion of corn starch to various temperatures, followed by its freezing and defrosting, on selected properties of re-formed starch pastes. A suspension of starch was heated to various temperatures ranging from 59 to 94°C, and afterwards frozen and defrosted. The differential scanning calorimetry (Mettler Toledo, 822E) thermal characteristics of starch pre-heated to temperatures not inducing complete pasting revealed transitions of: (I) retrograded amylopectin, (II) non-pasted starch, (III) amylose-lipid complexes, (IV) retrograded amylose, and (V) highly thermostable starch structures. The application of higher temperatures during heating caused disappearance of transitions II and V. The increase of pre-heating temperature induced firstly a decrease and then stabilization of the swelling power as well as a successive decrease in starch solubility. Pastes pre-heated to temperatures over 79°C contained large macroparticles that were increasing viscosity of the re-formed starch paste (their size was positively correlated with viscosity value).

Sign in / Sign up

Export Citation Format

Share Document